La recepción de los conceptos bergsonianos de Duración, Memoria e Impulso vital en los escritos de Gilles Deleuze sobre el cine

Màster Oficial en Estudis Avançats en Història de l'Art. Facultat de Geografia i Història de la UB. Curs: 2013-2014, Tutor: Josep Casals NavasEn Le Bergsonisme, un escrito publicado en 1966, Gilles Deleuze (1925- 1995) afirma que Duración, Memoria e Impulso vital señalan las grandes etapas de la filosofía de Henri-Louis Bergson (1859-1941)1 . Este trabajo tratará de indagar en qué medida las reflexiones que Deleuze elabora en su análisis acerca de la experiencia cinematográfica –Cinéma 1. L’Imagemouvement (1983) y Cinéma 2. L’Image-temps (1985)– son deudoras de estos conceptos bergsonianos. Deleuze, además del escrito ya citado, publicó varios textos sobre Bergson. En 1956 escribió dos artículos2 y en 1957 publicó una colección de textos escogidos de las obras de Bergson3. Mathias Vollet sostiene, al referirse a L’Image-mouvement y L’Image-temps, que “los conceptos claves que Deleuze utiliza son conceptos suyos; quizás son bergsonianos, pero no de Bergson”4. “La filosofía es el arte de formar, de inventar, de fabricar los conceptos”, dirá el propio Deleuze en Qu'est-ce que la philosophie?5 En el último pasaje de L’Image-temps, recuerda que escribe sobre conceptos del cine, no de teorías sobre el cine. En realidad, Deleuze afirma “que ya no cabe preguntarse «¿qué es el cine?», sino, «¿qué es la filosofía?

Els productes secundaris de les plantes

¿Quines són les funcions per a les plantes i les aplicacions per a l'home dels alcaloides i altres productes secundaris dels vegetals

Spontaneous motility of actin lamellar fragments

We show that actin lamellar fragments driven solely by polymerization forces at the bounding membrane are generically motile when the circular symmetry is spontaneously broken, with no need of molecular motors or global polarization. We base our study on a nonlinear analysis of a recently introduced minimal model [Callan-Jones et al Phys. Rev. Lett. 100, 258106 (2008)]. We prove the nonlinear instability of the center of mass and find an exact and simple relation between shape and center-of-mass velocity. A complex subcritical bifurcation scenario into traveling solutions is unfolded, where finite velocities appear through a nonadiabatic mechanism. Examples of traveling solutions and their stability are studied numericall

Homoclinic snaking in bounded domains

Homoclinic snaking is a term used to describe the back and forth oscillation of a branch of time-independent spatially localized states in a bistable, spatially reversible system as the localized structure grows in length by repeatedly adding rolls on either side. On the real line this process continues forever. In finite domains snaking terminates once the domain is filled but the details of how this occurs depend critically on the choice of boundary conditions. With periodic boundary conditions the snaking branches terminate on a branch of spatially periodic states. However, with non-Neumann boundary conditions they turn continuously into a large amplitude filling state that replaces the periodic state. This behavior, shown here in detail for the Swift-Hohenberg equation, explains the phenomenon of “snaking without bistability”, recently observed in simulations of binary fluid convection by Mercader, Batiste, Alonso and Knobloch (preprint)

Computational homogenization of higher-order electro-mechanical materials with built-in generalized periodicity conditions

We present a formulation for high-order generalized periodicity conditions in the context of a high-order electromechanical theory including flexoelectricity, strain gradient elasticity and gradient dielectricity, with the goal of studying periodic architected metamaterials. Such theory results in fourth-order governing partial differential equations, and the periodicity conditions involve continuity across the periodic boundary of primal fields (displacement and electric potential) and their normal derivatives, continuity of the corresponding dual generalized forces (tractions, double tractions, surface charge density and double surface charge density). Rather than imposing these conditions numerically as explicit constraints, we develop an approximation space which fulfils generalized periodicity by construction. Our method naturally allows us to impose general macroscopic fields (strains/stresses and electric fields/electric displacements) along arbitrary directions, enabling the characterization of the material anisotropy. We apply the proposed method to study periodic architected metamaterials with apparent piezoelectricity. We first verify the method by directly comparing the results with a large periodic structure, then apply it to evaluate the anisotropic apparently piezoelectricity of a geometrically polarized 2D lattice, and finally demonstrate the application of the method in a 3D architected metamaterial

Sistema d'adquisició de temperatures de 2 canals via R.F.

Curs 2011-2012Poder mesurar i enregistrar diferents tipus de magnituds com pressió, força, temperatura etc. s’ha convertit en una necessitat per moltes aplicacions actuals. Aquestes magnituds poden tenir procedències molt diverses, tals com l’entorn, o poden ser generades per sistemes mecànics, elèctrics, etc. Per tal de poder adquirir aquestes magnituds, s’utilitzen els sistemes d’adquisició de dades. Aquests sistemes, prenen mostres analògiques del món real, i les transformen en dades digitals que poden ser manipulades per un sistema electrònic. Pràcticament qualsevol magnitud es pot mesurar utilitzant el sensor adient. Una magnitud molt utilitzada en sistemes d’adquisició de dades, és la temperatura. Els sistemes d’adquisició de temperatures estan molt generalitzats, i podem trobar-los com a sistemes, on l’objectiu és mostrar les dades adquirides, o podem trobar-los formant part de sistemes de control, aportant uns inputs necessaris per el seu correcte funcionament, garantir-ne l’estabilitat, seguretat etc. Aquest projecte, promogut per l’empresa Elausa, s’encarregarà d’adquirir, el senyal d’entrada de 2 Termoparells. Aquests mesuraran temperatures de circuits electrònics, que es trobaran dintre la càmera climàtica de Elausa, sotmesos a diferents condicions de temperatura, per tal de rebre l’homologació del circuit. El sistema haurà de poder mostrar les dades adquirides en temps real, i emmagatzemar-les en un PC que estarà ubicat en una oficina, situada a uns 30 m de distància de la sala on es farà el test. El sistema constarà d’un circuit electrònic que adquirirà, i condicionarà el senyal de sortida dels termoparells, per adaptar-lo a la tensió d’entrada d’un convertidor analògic digital, del microcontrolador integrat en aquesta placa. Seguidament aquesta informació, s’enviarà a través d’un mòdul transmissor de radiofreqüència, cap al PC on es visualitzaran les dades adquirides. Els objectius plantejats són els següents: - Dissenyar el circuit electrònic d’adquisició i condicionament del senyal. - Dissenyar, fabricar i muntar el circuit imprès de la placa d’adquisició. - Realitzar el programa de control del microcontrolador. - Realitzar el programa per presentar i desar les dades en un PC. - El sistema ha d’adquirir 2 temperatures, a través de Termoparells amb un rang d’entrada de -40ºC a +240ºC - S’ha de transmetre les dades via R.F. Els resultats del projecte han estat satisfactoris i s’han complert els objectius plantejats.Measure and register different magnitude types such as, pressure, force, temperature etc. has become a necessity for much kind of currently applications. These magnitudes could come from different sources, such as the real world, or they could be generated from mechanical, electrical systems etc. In order to measure and register the value of these magnitudes, data acquisition systems are used. These systems take analog samples from the environment, and transform them to digital data in order to be processed by an electronic system. Using the correct sensor, almost every environment magnitude could be measured. Of all this magnitudes, one of the mainly used in data acquisition systems, is temperature. Temperature data acquisition systems could be final systems, with the main target of showing acquired data, or they could be a part of a control system, with the target of giving acquired date as a system input in order to control, or permit the correct system performance. This project is promoted by Elausa, an electronics design and manufacturing company, and its target is acquiring the electrical signal input of 2 thermocouples. These thermocouples will measure the temperature of electronic devices located inside a climatic camera of this company, and they will be involved into different temperature conditions. This system has to show acquired data in real time, and save this data in a PC. This PC will be located in a room outside the place where the test will be done, at a distance of 30m. This system, will have an electronic circuit that will acquire and adapt the input thermocouples signals, to the input range of the digital to analog microcontroller converter, which will be integrated in the acquisition PCB. The next point will be to send this data from a R.F. transmission module, to a personal computer. The main target of this project is: - Design the hardware that could acquire, and adapt input data. - Design and build the acquisition PCB. - Design the software of the microcontroller. - Design PC software. - The system has to acquire 2 temperature magnitude using thermocouples sensors, with a temperature range from -40ºC to +240ºC. - Acquired data should be transmitted via R.F. Project results have been satisfied and proposed objectives have been fulfilled.Director/a: Agustí Rifà i CayuelaAvalador/a: Ramon Reig Bolañ

Unraveling the hidden complexity of quasideterministic ratchets: random walks, graphs, and circle maps

Brownian ratchets are shown to feature a nontrivial vanishing-noise limit where the dynamics is reduced to a stochastic alternation between two deterministic circle maps (quasideterministic ratchets). Motivated by cooperative dynamics of molecular motors, here we solve exactly the problem of two interacting quasideterministic ratchets. We show that the dynamics can be described as a random walk on a graph that is specific to each set of parameters. We compute point by point the exact velocity-force V ( f ) function as a summation over all paths in the specific graph for each f , revealing a complex structure that features self-similarity and nontrivial continuity properties. From a general perspective, we unveil that the alternation of two simple piecewise linear circle maps unfolds a very rich variety of dynamical complexity, in particular the phenomenon of piecewise chaos, where chaos emerges from the combination of nonchaotic maps. We show convergence of the finite-noise case to our exact solution